For months, Jackie Curtiss and Rob Matz (seen here as their avatars) continued their online courtship by spending romantic virtual nights together.

On their first date, set up through a mutual friend, Jackie Curtiss and Rob Matz met at a cowboy bar in Vancouver. Matz dyed his hair silver and Curtiss put on a pair of tight jeans to impress. They downed some drinks, hugged and fell for each other instantly. For their next date, Matz wanted to really stun her, so instead of going to a movie, they climbed to the top of a building and went roof jumping.

That is, virtual roof jumping, as well as virtual hugging in virtual Vancouver, because Matz and Curtiss met in Utherverse, a popular online 3-D universe where players interact in virtual cities, bars and, well, do pretty much anything else you can do in the real world, including have virtual sex.

“We lived together pretty much since the moment we met in a virtual sense,” says Matz, 28. Meanwhile, Curtiss, 32, calls Matz her “knight in shining pixels.”

This digital romance may seem like a harmless fantasy, but falling for an online persona whom you’ve never met has real consequences. First of all, your new true love might not even exist.

Just look at Notre Dame linebacker Manti Te’o, who became smitten in 2009 when a woman “pursued him” on Facebook and then suddenly “died” in September 2012. It turned out the woman was invented by a friend of his — and Te’o fell for an avatar, leading to nationwide scorn and ridicule.

People wondered out loud: How could someone like Te’o — a good-looking star athlete at a top-tier school — fall in love with a picture?

Experts say it can happen to anyone, and it’s happening more often these days — especially to dreamer types who make easy targets.

“It’s the same population that likes to go see romantic comedies,” says Max Joseph, co-host of MTV’s “Catfish,” which investigates Web romances to find out whether the people involved are legit. (They’re often not.) “Anyone who believes in love and wants it to happen to them is susceptible.”

Robert Epstein, a senior research psychologist at the American Institute for Behavioral Research and Technology, understands the feeling firsthand. Even though Epstein is a computer-intelligence expert, he found himself chatting online seven years ago with a woman who, after three months, he realized was not a sexy Russian love interest, but a chatbot programmed to auto-reply.

“It’s crazy because I’m supposedly an expert in this area,” he says. “It is really, really easy to be fooled.”

Online relationships have been around as long as the first AOL chat room, but technological advances in recent years have changed their status to “it’s complicated.” Epstein estimates hundreds of thousands of people online are chatting with someone who is not whom they appear to be. The phenomenon is “out of control,” adds Nev Schulman, the host and executive producer of MTV’s “Catfish” and the star of the 2010 “Catfish” film that inspired the series.

“Many of us, without intentionally doing so, curate and control our online identity, very much in a way that people have been using clothing, plastic surgery or makeup to look their best and to attract people,” he says. “The temptation is there to make yourself a little bit better here, a little bit better there . . . and it grows and grows.”

It’s a freakish minefield for Internet users that has grown trickier with new technologies.

Jessica, a 31-year-old who lives in Brooklyn and works in retail and didn’t want her last name used in order to hide her online past, found this out the hard way.

Being a social outcast in high school drove her to punk and hardcore music chat rooms. She befriended a guy for a year before they finally met in person, and it was a shock.

“I was totally scared,” she says. “He was overly affectionate. We were like oil and water. It was like two different relationships, two different sets of people, in the flesh and on the keyboard.”

She still meets people on message boards and through Facebook, though she’s much more wary about it now.

“I’m still two people — I have an online persona and I have a real-life persona — sometimes they blend and sometimes they never come together,” she says. “You’re lucky if you find someone that you fit with, even if you never meet them face to face.”

When he was in high school, Chris Zaldua had a stutter. But then he discovered chatting by text, and with it, plenty of romantic possibilities.

“That kind of blew my mind,” he says. “It was a whole new world for me.”

Zaldua, now 28 and living in San Francisco, wooed three women in online chat rooms, going on to date all of them in real-life, including one for five years. Even so, he says the Web wasn’t the best way to start a love affair.

“We were similar in certain ways, but a terrible match romantically,” he says of his most long-term relationship. “Had we met in person and been able to spend some time together in proximity, I probably would have been able to find [that] out.”

Teenagers particularly seek out friends on the Internet to compensate for anxiety or other disabilities, says Art Bowler, a psychologist who counsels people with online addiction. But it still doesn’t compare to the real-world version.

“The truest relationships are the ones that are most intimate in real life. You can actually live and find out what works, what doesn’t,” he says.

And scientific research confirms that your brain simply reacts to people differently when you see them in person.

It’s a phenomenon known as limbic resonance: When two people are face-to-face, your brain releases a bouquet of neurochemicals, which regulates emotions and physiological functions, says Hilarie Cash, founder of reSTART, the country’s only full-service rehab center devoted exclusively to Internet addiction.

“We need social relationships to feel good and function at our best. When people spend more and more time online . . . they’re not getting that need met in an adequate way,” says Cash.

The permanence of Twitter, YouTube and other services presents new dangers for today’s teens, says Joshua Rosenthal, a Manhattan clinical psychologist for young adults.

“There’s just a lot of education that needs to take place,” says Rosenthal, who recommends that parents talk to their children about how natural relationships develop over time. “The big risk for teenagers is they’re incredibly impulsive and don’t think before they act. Anything you can do to break that down before they act is a good thing.”

For Matz and Curtiss, though, their online hookup turned out to be more fulfilling than any of their real-world relationships, virtual make-out sessions and all. Curtiss says she was stuck in an “unhealthy” marriage when she met Matz on Utherverse. Months later, they arranged a real-world meeting in Destin, Fla., where she lived.

The connection was strong and immediate: Curtiss bear-hugged Matz so hard he nearly fell over. They’re now engaged.

“There are a lot of people who have a stigma about online dating. But honestly you can’t really [judge] unless you’re in that position,” says Curtiss. “If you find happiness, if an opportunity is there, grab it, because it might not happen again.”